Tuesday, 1 April 2014

Guest operating systems running on virtualised systems needs to cooperate with the underlying hypervisors when using virtualised resources. Virtio is a set of standard for disk and network virtualisation that is required to be installed on instances that runs on Openstack. The default Androidx86 kernel does not come with these modules installed. Also, you have to edit the source code of Androidx86 OS to detect the virtualised block devices. Otherwise you will see a screen with "Detecting Android-x86... (continuous dots :s)".

This is what you will see in androidx86 debug mode:

If you do not want to compile the source and set it up yourself. I have already created the image for you. Download it from here.

1. First, to compile the OS you have to initialise the build environment. Follow instructions here.

Wednesday, 12 March 2014

I have come across this issue a while ago on our Openstack testbed that as the amount of API calls increase, the delay when you do API calls increased. Then I discovered that Openstack does not clean the expired tokens automatically when you are using a SQL backend.

Wednesday, 29 January 2014

The most annoying bug that I came across when setting up Openstack Folsom was that, after creating the a virtual machine it was not able to reach the metadata service and I was not able to reach the virtual machine.

After days of debugging, I found out that it was not only me that was having the same issue. Finally it was reported as a known bug to the openstack developers.

https://bugs.launchpad.net/neutron/+bug/1091605

The problem seems to be that OpenvSwitch devices have been brought back up after after rebooting. Hence before I upgraded to Grizzily from Folsom, I created the following script and had it running at the boot-up in the network node.

Currently I am using Openstack Folsom, nova version 2013.1.4, Installed on Ubuntu 12.04. I upgraded my compute and network nodes's kernel to "Linux 3.2.0-58-generic". Since then, when I try to create an instance on a the compute nodes or when I restart the network node, the systems goes to Kernel panic.

The only fix for this issue I found, is to downgrade the kernel from "Linux 3.2.0-58-generic" to "Linux 3.2.0-55-generic" on all compute nodes and network node to keep things consistent. The controller nodes does not seem to be affected by this kernel bug.

Also make sure to install the header if the corresponding kernel, if you are installing the kernel. Or if you have already got "Linux 3.2.0-55-generic" kernel installed, then just change it to the default kernel in grub records.

First find out the index of the kernel in the grub records.

grep menuentry /boot/grub2/grub.cfg

Then the fist answer of the following question should help when editing the grub config.

I came across this error on Openstack Grizzily installed on Ubuntu 12.04 LTS, when I upgrade or degrade the linux kernel. So its very likely that you will get this error after running a "dist-upgrade" on your system.

The cause of this problem seem to be that when a different kernel is used, the openvswitch modules have not been built with it.

I came across this error on Openstack Folsom installed on Ubuntu 12.04 LTS, when I upgrade or degrade the linux kernel. So its very likely that you will get this error after running a "dist-upgrade" on your system.

The cause of this problem seem to be that when a different kernel is used, the openvswitch modules have not been built with it.